St. Maches was the sister of St.
Cadog. She lived the humble life of a shepherdess in the early 6th
century, but was killed by robbers who wished to steel her finest ram. St.
Tathyw built a church on the spot where she was killed in Merthyr Maches (Llanfaches,
Gwent) and had her body removed to his monastery at Caerwent.